Electromagnetic Transitions

Luca Salasnich

Emilio d’Emilio, Luigi E. Picasso

Emilio d’Emilio, Luigi E. Picasso

Adel Khalaf Hamoudi

The fluctuation properties of energy spectrum, electromagnetic transition intensities and electromagnetic moments in nucleus are investigated with realistic shell model calculations. We find that the spectral fluctuations of are consistent with the Gaussian orthogonal ensemble of random matrices. Besides, we observe a transition from an order to chaos when the excitation energy is increased and a clear quantum signature of the breaking of chaoticity when the single-particle energies are increased. The distributions of the transition intensities and of the electromagnetic moments are well described by a Porter-Thomas distribution. The statistics of electromagnetic transition intensities clearly deviate from a Porter-Thomas distribution (i.e., a transition towards regularity is observed) when the single-particle energies are increased whereas the statistics of electromagnetic moments are not affected by the change of the single-particle energies.

Raghwinder Singh Grewal, M. Pattabiraman

Abstract The influence of the closed transition on the neighboring and open transitions of the 87 Rb D 2 line, partially resolved under Doppler broadening, is studied at different ellipticities in the Hanle configuration with longitudinal and transverse magnetic field scans. We show that a sign reversal from an electromagnetically induced transparency (EIT) resonance to an electromagnetically induced absorption (EIA) resonance occurs with an increase in ellipticity for the transition in a transverse field scan. This transformation is not observed for a longitudinal field scan. These observations are attributed to the higher amplitude of the EIA resonance for the transition in transverse field scans for elliptical polarized light. The EIA character in the Hanle transmission profile of and transitions is enhanced (weakened) when the laser beam frequency is detuned towards (away from) the transition. We show by computation that at higher ellipticities, a transformation from an EIT to an EIA resonance for the transition occurs at low frequency shifts (towards the transition) in a transverse field scan.

Zeeshan Ali Safdar Jadoon, Aisar-ul Hassan, Heung‐Ryoul Noh +1 more

The effects of neighboring transitions through Doppler broadening on electromagnetically induced absorption (EIA) and electromagnetically induced transparency (EIT) for the D2 transition line in Rb atoms with respect to the same circular polarization configurations ( σ + − σ + ) of coupling and probe lasers have been investigated. Spectra for the open F g = 2 → F e = 2 transition of 87 Rb and the F g = 3 → F e = 2 and 3 transitions of 85 Rb exhibit EIA, resulting from the neighboring effect of F g = 2 → F e = 3 and F g = 3 → F e = 4 transitions, respectively. In contrast, EIT is observed for the open F g = 2 → F e = 1 transition of 87 Rb, which indicates greater hyperfine energy splittings of 87 Rb and weaker neighboring effects than those of 85 Rb. Based on the theoretical results, we can confirm that EIT in the case of F g > F e for 87 Rb and circular parallel polarization transforms into EIA due to the magnitude of the neighboring effects with a decrease in the hyperfine energy splittings.